Fig. S8

The combined effects of Zic2a depletion and Hh pathway hyperactivation on pax6a, fgf8a and spry4 expression. (A-L) Zic2a knockdown does not affect pax6a expression in the anterior retina (B, normal in 10/10 embryos). By contrast, overexpression of shha inhibits pax6a expression throughout the retina, most noticeably in the nasal retina (C, red arrow, 9/13 embryos). Embryos co-injected with shha mRNA and zic2aMO exhibit an overall reduction of pax6a in the retina, with a more pronounced clearing in the nasal retina (D, orange arrow, 12/12 embryos). fgf8a expression is expanded in zic2aMO-injected embryos (F, green arrow, 11/12 embryos). Similarly, ectopic fgf8a expression is observed in shha-mRNA-injected embryos (G, green arrow, 3/11 embryos). In shha mRNA plus zic2aMO injected embryos, dramatically increased ectopic fgf8a expression is observed (H, orange arrows, 4/12 embryos). spry4 expression is also expanded in zic2aMO-injected embryos (J, green arrow, 10/10 embryos). shha mRNA induces ectopic spry4 (K, green arrow, 11/13 embryos). Co-injection of shha mRNA and zic2aMO leads to a stronger expansion of spry4 expression than either single injection (L, orange arrow, 7/11 embryos). A-D are lateral views of isolated retina, anterior forward. E-L are lateral view, anterior to the left. E′-L′ are ventral views of the same embryos, anterior to the left. All embryos shown at prim-5.